On July 1st, 2021, Stanford's Department of Epidemiology & Population Health welcomed new Vice Chair John Witte (@johnwitte). Dr. Witte is a Professor of Epidemiology & Population Health and of Biomedical Data Science, and a member of the Stanford Cancer Institute. He will continue his groundbreaking work in the genetic epidemiology of prostate and other cancers, with an emphasis on reducing health disparities across diverse populations. This will include using genetic information to improve cancer screening and treatment at Stanford.
In this latest Spotlight interview with Communications and Public Relations Manager Katie M. Kanagawa, Dr. Witte tells a little about himself, including how he became a genetic epidemiologist and what he will be working on in the E&PH Department.
How did you first become interested in genetic epidemiology?
While in graduate school in engineering at UC Berkeley I had an opening in my schedule for an elective and happened upon an interesting looking epidemiology course. I took the course and was thrilled to discover the field of epidemiology, and how quantitative approaches could be applied to improving health. After completing a master’s degree at Cal, I pursued a PhD in epidemiology at UCLA, where I worked as a research assistant on a genetic epidemiology study of breast cancer. I found the investigation of genetic and environmental risk factors for cancer exciting, especially in light of the rapid technological advances in assaying the human genome combined with methodological advances to study design and analysis approaches.
I understand you will be continuing your research in the genetic epidemiology of prostate cancer. What first interested you in this area of research?
During my first faculty position—at Case Western Reserve University and the Cleveland Clinic—I became interested in prostate cancer because of the many unanswered questions regarding why particular tumors progress in a life-threatening manner and why men of African ancestry have higher incidence of and mortality from prostate cancer than other populations. This prompted my launching a series of genetic epidemiologic studies. One study of brothers both diagnosed with prostate cancer was the first to identify genetic loci linked to aggressive disease. Another was the first study of prostate tumor mutations among African-American men, which substantially differ from those observed in other populations and may help explain disparities in this common but complex disease.
What are some of the initiatives you will be participating in at Stanford?
One is a recently launched pilot study looking at incorporating polygenic risk scores—a summary of an individual’s estimated genetic predisposition to disease—into clinical practice. Initially focusing on risks of cardiovascular disease, breast cancer, and prostate cancer, this initiative represents an important advance in translating genetic epidemiologic discoveries to improve screening, prevention, and treatment of disease. I will be involved with developing and applying the polygenic risk scores. A potential obstacle here is the transferability of risk scores across different populations, which, if done incorrectly, could increase health disparities. To address this concern, my colleagues and I have just been named one of six sites awarded $38M total by the NIH to improve the utility of polygenic risk scores in diverse populations; our site’s grant is titled “Leveraging Diversity in Cancer Epidemiology Cohorts and Novel Methods to Improve Polygenic Risk Scores.”
I will also participate in a number of Epidemiology & Population Health initiatives, including expanding training, mentoring, and support of epidemiologists from diverse backgrounds at all levels, from undergraduate students to faculty.
What have been your greatest or fondest professional accomplishments?
In addition to new scientific discoveries, my most meaningful accomplishment has been mentoring the next generation of genetic epidemiologists. Working with trainees makes for an exciting and inspiring environment that enhances my own thinking and motivates developments in my own work. I find it gratifying to see mentees flourishing as scientists and educators themselves, and I hope that by training skilled and thoughtful researchers, I am indirectly contributing to future work that may enrich the well-being of many.